Why Does a Stock Go Down in Price When There is a Big Sell Off?

A reader asks: "Why does a stock go down in price when there is a big sell off or any selling for that matter? Meaning doesn't there have to be a buyer when there are sellers? So if people are buying when others are selling shouldn't that equal it out and the stock price stay the same?"

We discuss the question in "Why Does a Stock Go Down in Price When There is a Big Sell Off?"